Four men are accused of running a large-scale illegal-immigrant smuggling ring that used panga-style boats to transport the immigrants, according to federal authorities.

Last week, the smugglers dropped off illegal immigrants at a beach in Carlsbad in San Diego County and took them by van to a drop house in Anaheim, according to U.S. Immigration and Customs Enforcement.

Investigators with a multi-agency task force raided the apartment Friday and found nine illegal immigrants from Mexico, their clothes still wet and caked with sand, officials said.

Mario Echeverria, 24, a U.S. citizen who lives in Tijuana, was charged with being one of the leaders of the ring. Also charged were Mexican residents Javier Gomez-Dominguez, 30, the alleged caretaker of the drop house; Jose Sevilla, 26, the suspected captain of the boat; and Fernando Medina-Gonzalez, 43, who officials say was the navigator.

After an initial appearance in federal court, the four men were ordered detained and are expected to be arraigned in three weeks, said Thom Mrozek, spokesman for the U.S. attorney's office in Los Angeles.